The world's first "test tube baby" has paid tribute to IVF pioneer Professor Sir Robert Edwards saying that his "legacy will live on" after he died today aged 87.

Louise Brown, who was born on July 25, 1978 thanks to Sir Robert's work, said she thought of him as a "grandfather."

ITV News' Neil Connery reports:

Since her birth, more than five million babies have been conceived and delivered around the world using In-Vitro Fertilisation techniques.

His colleague gynaecologist Patrick Steptoe, with whom he developed IVF treatment in the 1960s and 1970s, died in 1988.

Sir Robert, who was knighted in 2011 the year after receiving a Nobel prize, died after a "long illness", his family said.

Ms Brown paid tribute to Sir Robert today, saying:

It was really sad to hear the news today. I have always regarded Robert Edwards as like a grandfather to me. His work, along with Patrick Steptoe, has brought happiness and joy to millions of people all over the world by enabling them to have children.

I am glad that he lived long enough to be recognised with a Nobel Prize for his work and his legacy will live on with all the IVF work being carried out throughout the world.

The thoughts of myself and my sister Natalie, who was also born through IVF, are with his family at this sad time.

Sir Robert and colleagues at Cambridge University succeeded in fertilising the human egg outside the body in 1969, which laid the foundations for Ms Brown's birth in 1978.

Edwards and Steptoe conducted their research in the face of hostile opposition from church leaders, governments, and sections of the media, and skepticism from scientific colleagues.